Building on the success of Phase l work, this Phase ll program proposes to advance a new generation of optical coherence tomography (OCT) technology based on the swept source (SS) Fourier-domain technique. The resultant bio-medical imaging system from this work, having the combined advantages in higher image quality and speed, will potentially replace the existing time-domain OCT configuration, and enable various pre-clinical and clinical applications including drug discovery, genomics, small animal imaging, in-vivo diagnosis of pathological diseases and early cancer formation in human tissue, 3-dimensional mapping, and real-time intrasurgical guidance. It is expected that the availability of new imaging modality should have wide spread impact in bio-medical research, education, and health care. The proposed program objectives are to (1) develop an innovative high-speed laser system that will form the core platform of a SS-OCT engine for bio-medical imaging, and (2) develop an OCT microscope system to demonstrate video rate imaging using the swept laser system. The key project aims will be to (a) generate a high-speed 1300nm swept-laser source capable of a 3dB lasing range of approximately 70nm, a linewidth of approximately 0.1 nm, an average output power approximately 10mW, and a sweep frequency of 16KHz, (b) develop optimum uniformfrequency trigger techniques, (c) integrate high-speed swept laser electronics and software platform, (d) design and optimize the SS-OCT fiber-optic Michelson interferometric system including incorporation of novel system topology to accomplish complex conjugate image resolution for 2x expansion of available imaging depth, (e) develop a SS-OCT engine with high-speed data acquisition & processing infrastructure, and (f) build a high-resolution (<10mu/m in tissue) and high-speed (16KHz A-scan, 500 lines/frame, 32 fps) SSOCT scanning microscope to perform high-speed imaging for characterization of system performance and for demonstration of real time in vivo cancer imaging.